1. Field of the Invention
The invention pertains to the field of nesting stacking containers. More particularly, the invention pertains to a nesting crate with hexagonal corners each having a support member for stacking.
2. Description of Related Art
Bins, crates, and other containers, especially those intended for industrial or commercial use, are employed to contain and/or transport a variety of products, parts or raw materials. Stackability of filled bins or crates is desirable for efficient use of space during transportation or storage of such goods. When stacked, it is important to ensure that the crates do not move laterally or slide off the next-lower crate. Stability of stacking is easily achieved with non-nesting crates. Nesting of empty crates is also desirable so that the crates occupy less space and are easily moved in bulk. Manifestly, however, nestability requires the crate to be wider at the top than at the bottom, precluding the type of stacking mentioned above.
Several nesting, stacking containers are known in the art. One method of achieving stackability of nesting containers consists of providing retractable laterally-projecting support members at the base of the container. An example is shown in U.S. Pat. No. 4,872,574, CONTAINER (Lam 1989), one embodiment of which includes rectangular extension members housed in slots at the four corners of the base and arranged to be slid outwardly to provide stability of stacked containers. Each extension member has a downwardly-projecting flange to prevent collapse of stacked containers by preventing excessive relative displacement in a lateral direction.
Another method of stacking nesting containers entails providing support members, such as flaps or rods, at the top rim of each container to support a similar container stacked above it. Several examples of such are shown in the art. In U.S. Pat. No. 4,872,574, referred to above, an alternate embodiment of the apparatus disclosed therein includes support protrusions fused onto the rim in four locations near the corners. These are not ideal, however, as their fusion to the top rim interferes with nesting of empty containers.
Such disadvantage is absent in devices where the support member rotates for positioning outside of the interior space of the container, as disclosed in U.S. Pat. No. 2,765,099, LUG BOX (Lively 1956). That patent shows a container having hinged wings or leaves connected to the upper edge of each end wall, which rotate about a hinge disposed at the top of the end wall. When the wings are placed in a vertical position the containers nest one within another; when they are placed in a horizontal position pointing inwardly from the top rim of the end wall, the containers stack one on top of another.
A similar approach is taken in U.S. Pat. Nos. 2,293,966, RECEPTACLE (Best 1942) and 3,659,743, PLASTIC NESTING AND STACKING CASE (Box 1972), but instead of wings or leaves, corner irons or brackets flip along an axis just below and parallel to the top rim of the end walls or side walls, to rest upon the side walls or end walls (respectively) and provide support for the crate stacked upon it. The brackets are flipped back to the outside of the container for nesting.
PCT international published application WO 89/09168, PCT/GB89/00303, CRATES FOR TRANSPORTING RUBBER BLOCKS OR SHEETS (Shaw, international publication date Oct. 5, 1989) discloses a stacking nesting crate having hinged support members located near the corner of the crate, each such member having a blade hinged about an axis parallel to the longitudinal axis of the top rim. When not in use, the blade extends outwardly downwardly extrinsic to the crate""s interior. When flipped, or rotated about its axis, the hinged support member lies in a substantially horizontal position extending inwardly towards the opposite side wall of the crate to support the base of an overlying crate. Although the support members are positioned near the corners, they are nevertheless embedded in the crate wall and extend outwardly perpendicularly therefrom. The disadvantage of such an arrangement is that the horizontal component of the downward/inward force vector resulting from stacking another crate on top is substantially perpendicular to the wall housing the support member, resulting in a risk of deformation of or breakage from the wall if the weight being supported becomes too heavy. There is additionally a risk of deformation or breakage of the half-square corner members, which are inherently weaker than corner members that are half-hexagonal in horizontal cross section (see below).
All of the above devices have square corners, whereby each corner has only two sides. Non-square corners, as for example semi-hexagonal corners, provide added strength to a container. U.S. Pat. No. 4,984,734, STACKABLE ARTICULATED CARTON TRAY APPARATUS (Zion 1991) discloses a stackable cardboard pizza carton with three-sided corners that are substantially hexagonal or octagonal in shape, to effectively retain a substantially circular pizza pie and support a similar carton stacked above it. The device is primarily designed for stacking of multiple food products for delivery to the consumer, and does not have a rigid frame.
In addition to square corners being inherently weaker than hexagonal corners, there are two additional benefits to hexagonal corners. First, hexagonal corners allow placement of the stacking-support member in the middle of the corner member instead of merely near the corner member or on one side of the corner member. This provides for extra support from all of the corner member""s sides-the middle side as well as the two outer sides of the semi-hexagon-of the weight placed on top. Second, when the crate is placed in the nesting configuration, the support blades extend outwardly downwardly to the corner rather than to the side or end of the crate. This means that the outwardly-downwardly extending support blades occupy a gap that the hexagonal corner carves out of the square corner that would otherwise be present, and so multiple stacks of nested crates can be placed side-by-side and/or end-to-end without the outwardly-downwardly extending support blade getting in the way. Finally, it is noted that with support blades placed in the middle of a hexagonal corner, in the stacking position the blades extend diagonally generally towards the opposite corner of the crate rather than toward the opposite side wall.
Accordingly, while nesting crates with support members for stackability are known in the art, none include non-square corners designed to provide added strength to the corner. A fortiori, none comprise support members extending from non-square corners for added stacking-support strength.
The present invention comprises a substantially rectangular crate having upwardly outwardly flaring collapsible side walls and end walls which terminate at the top in a top rim. The invented crate also includes a base with an upper surface and a lower surface, the lower surface preferably having spaced hollow feet each adapted to receive the blade of a forklift truck underneath each side or end wall. The invented crate further includes corner members disposed between each pair of adjacent walls. The corner members extend upwardly outwardly from the bottom of the crate and include three sides, preferably forming in cross section a semi-hexagon. Such corner members are hereinafter referred to as xe2x80x9chexagonal corners.xe2x80x9d
Each hexagonal corner has a stacking-support member disposed near the top thereof, which includes an H-shaped stacking-support housing and a support blade rotatably mounted upon the crossbar of the H. The support blade rotates about the cross bar, which lies along an axis parallel to the middle side of the corner when viewed in cross-section. The top of the xe2x80x98Hxe2x80x99 is preferably at approximately the same height as the top of the crate""s rim, with the crossbar being below that height.
In the nesting configuration, the crate""s support blades are rotated outwardly downwardly and remain extrinsic to the interior of the crate for nesting. In the stacking configuration, the blades are rotated about the crossbar of the stacking-support housing such that they point inwardly horizontally and diagonally across generally toward the center of the crate, to support the base of another crate. They are thus positioned within a plane parallel to the plane containing the top of the crate""s rim, but slightly below it due to the cross bar of the xe2x80x98Hxe2x80x99 being below the top of the xe2x80x98Hxe2x80x99. In this configuration another similar crate can be stacked upon the first crate for convenience of transport or storage of goods, with the bottom of the upper crate resting upon the support blades of the lower crate. Because the plane of the lower crate""s support blades is below the top edge of the crate""s rim, the upper crate is prevented from moving laterally or sliding off the crate beneath. For further stability of stacked crates, it is preferable that the feet of each crate have depressions or indentations that match the stacking-support blades of a crate below when the latter is in the stacking configuration.